Calculators Green Manure Calculator

How to use this calculator

Default values are provided for grain costs and cost of implementation. These inputs can be changed as required.

Required changes include "Number of Cereal Crops" after chosen rotation and grain yield.

Green Manure

Green Manure Cost ($/ha)

Number of Cereals after Green Manure

Yield following Green Manure (t/ha)

Cereal Cost ($/ha)

Grain Price ($/t)

Reduction in Yield after each year (%)

Break Crop Comparison

Legume Yield (t/ha)

Legume Cost ($/ha)

Legume Price ($/t)

Number of cereals after Break Crop

Yield following Break Crop (t/ha)

Cereal Cost ($/ha)

Grain Price ($/t)

Reduction in yield after each year (%)

Background

Green manuring is seen as a management option to improve the soil nutrient status for future seasons. Any crop can be used to green manure, but the most common options are legumes as an organic source of nitrogen. Brown manuring can refer to a chemical fallow or a sprayed out or unharvested crop. Whether a paddock is green or brown manured, the long term differences are very minor. No export of product occurs with either method, meaning all nutrients remain in the paddock for breakdown by the soil microbes.

This calculator provides a comparison of relative benefits between a green or brown manure phase and a grain crop within a defined rotational sequence. Results provide an indication of economic costs and benefits based on variable inputs. This calculator assumes the use of a legume crop.